Thursday, August 22, 2013

Reading List: Radical Abundance

Nanotechnology burst into public awareness with the publication
of the author's
Engines of Creation
in 1986. (The author coined the word
“nanotechnology” to denote engineering at
the atomic scale, fabricating structures with the atomic
precision of molecules. A 1974 Japanese paper had used
the term “nano-technology”, but with an entirely
different meaning.) Before long, the popular media were
full of speculation about nanobots in the bloodstream,
self-replicating assemblers terraforming planets or
mining the asteroids, and a world economy transformed
into one in which scarcity, in the sense we know it
today, would be transcended. Those inclined to darker
speculation warned of
“grey goo”—runaway
self-replicators which could devour the biosphere in 24
hours, or nanoengineered super weapons.

Those steeped in conventional wisdom scoffed at these
“futuristic” notions, likening them to earlier
predictions of nuclear power “too cheap to meter”
or space colonies, but detractors found it
difficult to refute Drexler's arguments that the systems he
proposed violated no law of physics and that the chemistry
of such structures was well-understood and predicted that,
if we figured out how to construct them, they would work.
Drexler's argument was reinforced when, in 1992, he
published
Nanosystems,
a detailed technical examination of molecular engineering
based upon his MIT Ph.D. dissertation.

As the 1990s progressed, there was an increasing consensus
that if nanosystems existed, we would be able to fabricate
nanosystems that worked as Drexler envisions, but the path
from our present-day crude fabrication technologies to
atomic precision on the macroscopic scale was unclear.
On the other hand, there were a number of potential pathways
which might get there, increasing the probability that
one or more might work. The situation is not unlike that
in the early days of integrated circuits. It was clear
from the laws of physics that were it possible to fabricate
a billion transistors on a chip they would work, but it was
equally clear that a series of increasingly difficult and
expensive to surmount hurdles would have to be cleared in
order to fabricate such a structure. Its feasibility then
became a question of whether engineers were clever enough to
solve all the problems along the way and if the market
for each generation of increasingly complex chips
would be large enough to fund the development of the
next.

A number of groups around the world, both academic and
commercial, began to pursue potential paths toward
nanotechnology, laying the foundation for the next step
beyond conventional macromolecular chemical synthesis.
It seemed like the major impediment to a rapid take-off
of nanotechnology akin to that experienced in the
semiconductor field was a lack of funding. But, as
Eric Drexler remarked to me in a conversation in the
1990s, most of the foundation of nanotechnology was
chemistry and “You can buy a lot of chemistry
for a billion dollars.”

That billion dollars appeared to be at hand in 2000,
when the U.S. created a billion dollar National
Nanotechnology Initiative (NNI). The NNI quickly
published an implementation plan which clearly stated
that “the essence of nanotechnology is the ability
to work at the molecular level, atom by atom, to create
large structures with fundamentally new molecular
organization”. And then it all went south. As is
almost inevitable with government-funded science and
technology programs, the usual grantmasters waddled up
to the trough, stuck their snouts into the new flow of
funds, and diverted it toward their research interests
which have nothing to do with the mission statement of
the NNI. They even managed to redefine “nanotechnology”
for their own purposes to exclude the construction of
objects with atomic precision. This is not to say that
some of the research NNI funds isn't worthwhile, but it's
not nanotechnology in the original sense of the word, and
doesn't advance toward the goal of molecular manufacturing.
(We often hear about government-funded research and
development “picking winners and losers”. In
fact, such programs pick only losers, since the winners will
already have been funded by the productive sector of the
economy based upon their potential return.)

In this book Drexler attempts a fundamental reset of the
vision he initially presented in
Engines of Creation. He concedes the word
“nanotechnology” to the hogs at the federal
trough and uses “atomically precise manufacturing”
(APM) to denote a fabrication technology which, starting from
simple molecular feedstocks, can make anything by
fabricating and assembling parts in a hierarchical fashion.
Just as books, music, and movies have become data
files which can be transferred around the globe in seconds,
copied at no cost, and accessed by a generic portable device,
physical objects will be encoded as fabrication instructions
which a generic factory can create as required, constrained
only that the size of the factory be large enough to assemble
the final product. But the same garage-sized factory can
crank out automobiles, motorboats, small aircraft, bicycles,
computers, furniture, and anything on that scale or smaller
just as your laser printer can print any document whatsoever
as long as you have a page description of it.

Further, many of these objects can be manufactured using
almost exclusively the most abundant elements on Earth,
reducing cost and eliminating resource constraints. And
atomic precision means that there will be no waste products
from the manufacturing process—all intermediate products
not present in the final product will be turned back into
feedstock. Ponder, for a few moments, the consequences of
this for the global economy.

In chapter 5 the author introduces a heuristic for visualising
the nanoscale. Imagine the world scaled up in size by a factor
of ten million, and time slowed down by the same factor. This
scaling preserves properties such as velocity, force, and mass,
and allows visualising nanoscale machines as the same size
and operating speed as those with which we are familiar. At this
scale a single transistor on a contemporary microchip would be
about as big as an iPad and the entire chip the size of Belgium.
Using this viewpoint, the author acquaints the reader with
the realities of the nanoscale and demonstrates that analogues
of macroscopic machines, when we figure out how to fabricate them,
will work and, because they will operate ten million times
faster, will be able to process macroscopic quantities of
material on a practical time scale.

But can we build them? Here, Drexler introduces the concept
of
“exploratory
engineering”:
using the known laws
of physics and conservative principles of engineering to
explore what is possible. Essentially, there is a landscape
of feasibility. One portion is what we have already accomplished,
another which is ruled out by the laws of physics. The rest is
that which we could accomplish if we could figure out how and
could afford it. This is a huge domain—given unlimited
funds and a few decades to work on the problem, there is
little doubt one could build a particle accelerator which circled
the Earth's equator. Drexler cites the work of
Konstantin Tsiolkovsky
as a masterpiece of exploratory engineering highly relevant to
atomically precise manufacturing. By 1903, working alone, he had
demonstrated the feasibility of achieving Earth orbit by means of a
multistage rocket burning liquid hydrogen and oxygen. Now,
Tsiolkovsky had no idea how to build the necessary engines,
fuel tanks, guidance systems, launch facilities, etc., but from
basic principles he was able to show that no physical
law ruled out their construction and that known materials would
suffice for them to work. We are in much the same position with
APM today.

The tone of this book is rather curious. Perhaps having
been burned by his earlier work being sensationalised, the
author is reserved to such an extent that on p. 275 he
includes a two pargraph aside urging readers to “curb
their enthusiasm”, and much of the text, while discussing
what may be the most significant development in human history
since the invention of agriculture, often reads like a white paper
from the Brookings Institution with half a dozen authors: “Profound
changes in national interests will call for a ground-up review of
grand strategy. Means and ends, risks and opportunities, the
future self-perceived interests of today's strategic competitors—none
of these can be taken for granted.” (p. 269)

I am also dismayed to see that Drexler appears to have bought in to
the whole anthropogenic global warming scam and repeatedly
genuflects to the whole “carbon is bad” nonsense.
The acknowledgements include a former advisor to the
anti-human World Wide Fund for Nature.

Despite quibbles, if you've been thinking “Hey, it's the
21st century, where's my nanotechnology?”, this
is the book to read. It chronicles steady progress on the
foundations of APM and multiple paths through which the intermediate
steps toward achieving it may be achieved. It is enlightening
and encouraging. Just don't get enthusiastic.